Harold, Charles, and Elisabeth (or Harry, Chuck, and Betty) are a trio of mischievous ghost children in there debut in Luigi's Mansion: Queen Boo the tried to turn the Secret Mine into an playhouse, but Luigi defeats theme and then they watch him defeat Queen Boo. they along with Nicholas appear in other Mario games after there debut unlike the other portrait ghosts.
Shortly after Luigi defeated Netellia the note on her table said "The last room in this mansion lurks among the attic, but be careful because the ghostly trio of Harold, Charles, and Elisabeth might destroy the Secret Mine and turn it into a playhousetic" and when Luigi and Polterpup leaves the mirror room they can hear there snoring all the way to the attic entry and when Luigi and Polterpup goes into the Attic and sees the trio they were fast asleep but then they got awoken by Polterpup licking theme and they believe Luigi did, so they got entered theme into there battle arena (witch is actually a play arena) and after defeating theme they escape and describs Luigi what happen and goes into the vault so they can finish there nap. they later go to Queen Boo's battle arena and watches Luigi battle Queen Boo. they later appear in the end credits were they steals Nicholas's food causing him to go into a rampage.